The metatarsophalangeal joints (MTP joints) are the joints between the metatarsal bones of the foot and the proximal bones (proximal phalanges) of the toes. They are condyloid joints, meaning that an elliptical or rounded surface (of the metatarsal bones) comes close to a shallow cavity (of the proximal phalanges).
The movements permitted in the metatarsophalangeal joints are flexion, extension, abduction, adduction and circumduction Metatarsophalangeal joint pain is a common cause of metatarsalgia. Metatarsophalangeal joint pain most commonly results from misalignment of the joint surfaces with altered foot biomechanics, causing joint subluxations, flexor plate tears, capsular impingement, and joint cartilage destruction (osteoarthrosis). Misaligned joints may cause synovial impingement, with minimal if any heat and swelling (osteoarthritic synovitis).
The phalanges (phalanx) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones.
The phalanges are the bones that make up the fingers of the hand and the toes of the foot. There are 56 phalanges in the human body, with fourteen on each hand and foot. Three phalanges are present on each finger and toe, with the exception of the thumb and large toe, which possess only two. The middle and far phalanges of the fourth and fifth toes are often fused together (symphalangism). The phalanges of the hand are commonly known as the finger bones. The phalanges of the foot differ from the hand in that they are often shorter and more compressed, especially in the proximal phalanges, those closest to the body.
A phalanx is named according to whether it is are proximal, middle, or distal and its associated finger or toe. The proximal phalanges are those that are closest to the hand or foot. In the hand, the prominent, knobby ends of the phalanges are known as knuckles. The proximal phalanges join with the metacarpals of the hand or metatarsals of the foot at the metacarpophalangeal joint or metatarsophalangeal joint. The intermediate phalanx is not only intermediate in location, but usually also in size. The thumb and large toe do not possess a middle phalanx. The distal phalanges are the bones at the tips of the fingers or toes. The proximal, intermediate, and distal phalanges articulate with one another through interphalangeal articulations.
Head is the distal end of the metatarsal or distal end. It is flattened from side to side. Head of each metatarsal articulates with respective phalanx to form metatarsophalangeal joint. A constriction proximal to head is called anatomical neck.
A Chinese finger trap (also known as a Chinese finger puzzle, Chinese thumb cuff, Chinese handcuffs and similar variants) is a gag toy used to play a practical joke on unsuspecting children and adults. The finger trap is a simple puzzle that traps the victim's fingers (often the index fingers) in both ends of a small cylinder woven from bamboo. The initial reaction of the victim is to pull their fingers outward, but this only tightens the trap. The way to escape the trap is to push the ends toward the middle, which enlarges the openings and frees the fingers.